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101.
Karolina Sulek Henrik Lauritz Frandsen Jørn Smedsgaard Thomas Hjort Skov Andrea Wilcks Tine Rask Licht 《Metabolomics : Official journal of the Metabolomic Society》2012,8(2):244-252
Lactobacillus acidophilus NCFM is a well known microorganism from the genomic and probiotic point of view. In order to analyze the potential interactions
of NCFM with the surrounding environment, in vitro tests with the metabolic footprinting approach were performed. It was found
that NCFM increased the concentration of lactic acid, succinic acid, adenine and arginine in the medium. The metabolism of
NCFM did not change significantly between pH 5 and 7, suggesting that other environmental factors than pH might have bigger
impact on its colonization throughout the gastrointestinal tract. 相似文献
102.
Rasmussen LG Winning H Savorani F Ritz C Engelsen SB Astrup A Larsen TM Dragsted LO 《Genes & nutrition》2012,7(2):281-293
There is a need for a tool to assess dietary intake related to the habitual dietary glycaemic index (GI) and fibre in groups with large numbers of individuals. Novel metabolite-profiling techniques may be a useful approach when applied to human urine. In a long-term, controlled dietary intervention study, metabolomics were applied to assess dietary patterns. A targeted approach was used to evaluate the effects on urinary C-peptide excretion caused by the dietary treatments. Seventy-seven overweight subjects followed an 8-week low-calorie diet (LCD) and were then randomly assigned to a high-GI or low-GI diet for 6 month during which they completed 24-h urine collections at baseline (prior to the 8-week LCD) and after randomisation to the dietary intervention, at month 1, 3 and 6, respectively. Metabolite profiling in 24-h urine was performed by 1H NMR and chemometrics. Partial least squares (PLS) analysis indicated that urinary formate could discriminate between high-GI and low-GI diets (correlation coefficient r = 0.82), and this finding was confirmed statistically (P = 0.01). PLS analysis also indicated that urinary hippurate could be associated with fibre intake, but this finding was not confirmed statistically. No associations between GI and urinary C-peptide were found. Our results emphasise that application of metabolomics is useful in the assessment of dietary exposure related to dietary GI and fibre seen at group level in a nutritional metabolomic study of human urine. As our design allowed for large variations in individually selected food items, biomarkers identified at group level may be interpreted as more general and robust markers, largely not confounded with markers from single dietary factors. 相似文献
103.
Skov L Beurskens FJ Zachariae CO Reitamo S Teeling J Satijn D Knudsen KM Boot EP Hudson D Baadsgaard O Parren PW van de Winkel JG 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(1):669-679
IL-8 is a chemokine that has been implicated in a number of inflammatory diseases involving neutrophil activation. HuMab 10F8 is a novel fully human mAb against IL-8, which binds a discontinuous epitope on IL-8 overlapping the receptor binding site, and which effectively neutralizes IL-8-dependent human neutrophil activation and migration. We investigated whether interference in the cytokine network by HuMab 10F8 might benefit patients suffering from palmoplantar pustulosis, a chronic inflammatory skin disease. Treatment of patients with HuMab 10F8 was well tolerated and significantly reduced clinical disease activity at all five endpoints, which included a >or=50% reduction in the formation of fresh pustules. IL-8 neutralization was monitored at the site of inflammation by assessing exudates of palmoplantar pustulosis lesions. HuMab 10F8 sequestered IL-8 in situ, as observed by rapid dose-dependent decreases of IL-8 concentrations immediately following Ab infusion. These data demonstrate a critical role for IL-8 in the pathophysiology of palmoplantar pustulosis. HuMab 10F8 is capable of interrupting IL-8 activity in vivo and represents a candidate for treatment of inflammatory diseases and other pathological conditions associated with IL-8 overproduction. 相似文献
104.
Petersen RK Madsen L Pedersen LM Hallenborg P Hagland H Viste K Døskeland SO Kristiansen K 《Molecular and cellular biology》2008,28(11):3804-3816
Cyclic AMP (cAMP)-dependent processes are pivotal during the early stages of adipocyte differentiation. We show that exchange protein directly activated by cAMP (Epac), which functions as a guanine nucleotide exchange factor for the Ras-like GTPases Rap1 and Rap2, was required for cAMP-dependent stimulation of adipocyte differentiation. Epac, working via Rap, acted synergistically with cAMP-dependent protein kinase (protein kinase A [PKA]) to promote adipogenesis. The major role of PKA was to down-regulate Rho and Rho-kinase activity, rather than to enhance CREB phosphorylation. Suppression of Rho-kinase impaired proadipogenic insulin/insulin-like growth factor 1 signaling, which was restored by activation of Epac. This interplay between PKA and Epac-mediated processes not only provides novel insight into the initiation and tuning of adipocyte differentiation, but also demonstrates a new mechanism of cAMP signaling whereby cAMP uses both PKA and Epac to achieve an appropriate cellular response. 相似文献
105.
106.
Anja Pinborg Anne Loft Lone Schmidt Gorm Greisen Steen Rasmussen Anders Nyboe Andersen 《BMJ (Clinical research ed.)》2004,329(7461):311
Objective To compare neurological sequelae in twins born after assisted conception with singletons after assisted conception and naturally conceived twins and to assess neurological sequelae in children conceived after in vitro fertilisation (IVF) compared with intracytoplasmic sperm injection (ICSI).Design Controlled, national register based, cohort study.Participants Twins (n = 3393) and singletons (n = 5130) conceived by using assisted reproductive technologies and naturally conceived twins (n = 10 239) born in Denmark between 1995 and 2000. The children''s age at time of follow up was 2-7 years.Data sources Children were identified by cross linkage of the national medical birth registry and the national registry for in vitro fertilisation. Neurological and psychiatric diagnoses were retrieved from the national patients'' registry and the Danish psychiatric central registry.Main outcome measures Neurological sequelae, defined as cerebral palsy, mental retardation, severe mental developmental disturbances, and retarded psychomotor development. Further we made separate analyses on the specific cerebral palsy diagnosis.Results The crude prevalence rates per 1000 of neurological sequelae in twins and singletons after assisted conception and in naturally conceived twins were 8.8, 8.2, and 9.6, and of cerebral palsy 3.2, 2.5, and 4.0, respectively. In twins after assisted conception compared with control twins, the odds ratios of neurological sequelae and specifically of cerebral palsy, adjusted for child sex and year of birth, were 0.9 (95% confidence interval 0.6 to 1.4) and 0.8 (0.4 to 1.6), respectively. The corresponding odds ratios for twins after assisted conception compared with singletons after assisted conception were 1.1 (0.7 to 1.7) for neurological sequelae and 1.3 (0.6 to 2.9) for cerebral palsy. The odds ratio of neurological sequelae in children conceived by ICSI was 0.9 (0.5 to 1.7) ν children conceived by IVF.Conclusions Twins from assisted conception have a similar risk of neurological sequelae as their naturally conceived peers and singletons from assisted conception. Children born after ICSI have the same risk of neurological sequelae as children born after IVF. 相似文献
107.
Verocytotoxin-Producing Escherichia coli in Wild Birds and Rodents in Close Proximity to Farms
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Eva Mller Nielsen Marianne N. Skov Jesper J. Madsen Jens Lodal Jrgen Brchner Jespersen Dorte L. Baggesen 《Applied microbiology》2004,70(11):6944-6947
Wild animals living close to cattle and pig farms (four each) were examined for verocytotoxin-producing Escherichia coli (VTEC; also known as Shiga toxin-producing E. coli). The prevalence of VTEC among the 260 samples from wild animals was generally low. However, VTEC isolates from a starling (Sturnus vulgaris) and a Norway rat (Rattus norvegicus) were identical to cattle isolates from the corresponding farms with respect to serotype, virulence profile, and pulsed-field gel electrophoresis type. This study shows that wild birds and rodents may become infected from farm animals or vice versa, suggesting a possible role in VTEC transmission. 相似文献
108.
Rasmussen LC Oliveira CL Jensen JM Pedersen JS Sperling-Petersen HU Mortensen KK 《Biochemistry》2008,47(20):5590-5598
Initiation of protein synthesis in bacteria involves the combined action of three translation initiation factors, including translation initiation factor IF2. Structural knowledge of this bacterial protein is scarce. A fragment consisting of the four C-terminal domains of IF2 from Escherichia coli was expressed, purified, and characterized by small-angle X-ray scattering (SAXS), and from the SAXS data, a radius of gyration of 43 +/- 1 A and a maximum dimension of approximately 145 A were obtained for the molecule. Furthermore, the SAXS data revealed that E. coli IF2 in solution adopts a structure that is significantly different from the crystal structure of orthologous aIF5B from Methanobacterium thermoautotrophicum. This crystal structure constitutes the only atomic resolution structural knowledge of the full-length factor. Computer programs were applied to the SAXS data to provide an initial structural model for IF2 in solution. The low-resolution nature of SAXS prevents the elucidation of a complete and detailed structure, but the resulting model for C-terminal E. coli IF2 indicates important structural differences between the aIF5B crystal structure and IF2 in solution. The chalice-like structure with a highly exposed alpha-helical stretch observed for the aIF5B crystal structure was not found in the structural model of IF2 in solution, in which domain VI-2 is moved closer to the rest of the protein. 相似文献
109.
K. Skamstrup Hansen C. Bindslev-Jensen P. Stahl Skov S. H. Sparholt G. Nordskov Hansen N. R. Niemeijer H. -J. Malling L. K. Poulsen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,756(1-2)
The aim of the study was to standardize and evaluate technically optimized food allergen extracts for use in skin prick test (SPT). The standardization procedure comprised 36 allergic histories in 32 food allergic patients with 21 healthy, non-atopic individuals serving as controls. The patients had a history of allergic symptoms upon ingestion of either cow’s milk (n=3), hen’s egg (n=9), wheat (n=4), hazelnut (n=14) or cod (n=6). They also had specific IgE in serum to the food in question and a positive SPT with a fresh preparation of the food. The diagnosis had been confirmed by a double-blind, placebo-controlled food challenge, except for the hazelnut-allergic patients. The controls were subjected to an open food challenge with all the foods to ensure tolerance. The standardization was performed by means of titrated SPT in accordance with the guidelines on biological standardization from the Nordic Council on Medicine. Regression analysis of the skin wheal areas was performed for each patient and the median protein concentration of allergen preparation (median Ch10) eliciting a wheal area of the same size as histamine 10 mg/ml was calculated. The median Ch10 was 0.56 mg/ml for milk, 0.88 mg/ml for egg, 5.4 mg/ml for wheat, 2.1 mg/ml for hazelnut and 0.017 mg/ml for the cod extract. The sensitivity of the median Ch10 estimated from the SPT data was 1 for milk, 0.98 for egg, 1 for wheat, 1 for hazelnut and 0.87 for the cod extract. The allergenic activity of the hazelnut extract was further investigated by leukocyte histamine release (HR) and immunoblotting experiments using sera from 27 hazelnut allergic patients. The clinical sensitivity of the optimized hazelnut extract evaluated by HR was 0.78 compared to 0.30 for a commercially available hazelnut extract (Soluprick). Immunoblotting results showed a stronger IgE binding capacity and additional IgE-binding bands of the optimized hazelnut extract compared with the Soluprick extract. 相似文献
110.
The native palm flora of Ecuador consists of 129 taxa, including at least 69 species used by rural people, 19 of which are
exploited commercially. This paper integrates bioclimatic modeling of palm distribution and quantitative ranking through pair-wise
comparisons of species as a tool to evaluate and map the importance of 14 taxa of commercially exploited palms in Ecuador
based on criteria of harvest values, sustainability, vegetation cover and population density. The ranking procedure could
find broad application within ethnobotany and economic botany. Results show that extraction of palm products, economically
speaking, is most important in the heavily deforested and populated coastal lowland. 相似文献